Researchers have found that ocean noise is a big problem for underwater life. Human activities like shipping, naval exercises, and oil exploration pump the oceans full of loud noises that marine species haven't adapted to. So when the global economy ground to a halt due to COVID-19, did the ocean quiet down?

Links

Dugald J. M. Thomson and David Barclay. "Real-time observations of the impact of COVID-19 on underwater noise." The Journal of the Acoustical Society of America 147: 3390 (2020).

Rosalind M. Rolland, et al. "Evidence that ship noise increases stress in right whales." Proc. R. Soc. B. 279: 2363–2368 (2012).